LNG holds great promise as a transportation fuel for two principal reasons. First, its use results in significant reductions in SOx, NOx, CO2 and particulate emissions. Second, increased use of LNG, more specifically natural gas, as a transportation fuel, replacing traditional distillates such as gasoline and diesel fuel, has the added, but no less important, benefit of reducing dependency on crude oil, most importantly imported crude oil, and easing the burden on refining capacity.
The emission reductions exceed even the most far-reaching emissions regulations, without the need for post combustion exhaust gas treatment methodologies or other emissions systems that degrade engine efficiency. The use of LNG as a transportation fuel for city fleet vehicles, dedicated trucking routes, and even rail locomotives has been demonstrated with a high degree of success, but with limited implementation. The success of LNG as a liquid fuel also applies to vessels—including harbor tugs, ferries, supply vessels, short-sea shipping “roll-on/roll-off” and container vessels, and deep-sea vessels—for in-port and coastal power requirements. The technology is well established, with a number of noteworthy vessels in service and under construction that utilize LNG as propulsion fuel. Based on these early successes, the marine industry is evaluating wider application of LNG as an environmentally friendly marine fuel, replacing heavy fuel oils and light distillate fuels for ocean, coastal, and harbor service.
What is needed to increase the use of LNG as a transportation fuel in the U.S. and elsewhere is the development of a coherent LNG distribution infrastructure. Without such an infrastructure, the use of LNG as a fuel will be confined to local niche markets only, and thus it will never realize its true potential. Today, LNG, as a transportation fuel, is generally produced in limited quantities in the U.S. by liquefying pipeline gas, in small-scale liquefaction plants, in highly localized areas. This is not an efficient approach, and it will not allow LNG to reach its full potential as a highly desirable, energy dense, liquid fuel for both transportation and non-transportation uses.
A traditional role for LNG is the transportation of large volumes of natural gas over long distance ocean routes. The natural gas is liquefied to a cryogenic liquid at a location near the gas source, often in remote areas. The LNG is then loaded in large, specialized tankers for the ocean transit to the destination or re-gasification facility. At the destination facility, the LNG is unloaded from the tanker to tanks on shore. From the shore based tank storage, the LNG is then increased in pressure to the required downstream pressure and re-gasified and consumed at or near the destination facility or distributed to the end user by conventional pipeline. Although an efficient transportation system and method to deliver natural gas from remote sources of supply, this system does not provide for the efficient distribution of LNG as an energy dense liquid fuel to the transportation and power generation industries.
In view of the foregoing background, it is an object of the present invention to provide a critical missing link. That link will enable existing LNG terminals—liquefaction, regasification or other—in various locations throughout the world, to connect commercially to the extensive intermodal transportation systems throughout the world to implement safe and reliable LNG fuel supply distribution networks. This will support and hasten the use of LNG as an alternative fuel to power transportation assets, electric generating facilities, and other facilities that are capable of using natural gas as a fuel or feedstock. The anticipated results of making LNG more widely available will be the conversion from heavy and light distillate fuel oils to natural gas providing significant, near-term, emissions reductions; reduced dependency on crude oil; and reduced demand for crude oil refining capacity.